Milwaukee weather in September: Milwaukee, Wisconsin: normal highs, lows, rain and records for September
Milwaukee in September has a normal high of 74°F and a normal low of 56°F, a daily mean of 65°F, falling from 78°F on the 1st to 68°F by the 30th. Measurable precipitation falls on 9 days in a normal September, 3.16 inches in all. (NOAA 1991-2020 normals)
In metric: a normal high of 23°C and low of 14°C, 80 mm of precipitation in September.
- NOAA stationMilwaukee Mitchell Airport
- Station IDUSW00014839
- Location42.95°N 87.90°W
- Elevation670 ft (204 m)
- From the center8 miles
- Population563,531
- Jan 31° 17°
- Feb 34° 20°
- Mar 44° 29°
- Apr 55° 38°
- May 67° 48°
- Jun 77° 58°
- Jul 82° 65°
- Aug 80° 64°
- Sep 74° 56°
- Oct 61° 45°
- Nov 48° 33°
- Dec 36° 23°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
How warm is Milwaukee in September?
The normal high is 74°F and the normal low 56°F, for a daily mean of 65.0°F. September is 7.3°F cooler than August and 12.0°F warmer than October. September is the 4th warmest month of the year in Milwaukee and the 6th wettest. Across the month the normal high falls 10°F, from 78°F on September 1 to 68°F on September 30. From one year to the next September's mean temperature typically moves about 2.4°F either way (NOAA's standard deviation), so roughly two Septembers in three average between 63°F and 67°F.
Bars above: each day's normal high to low. Columns below: the chance of 0.01 inch or more of precipitation that day, on a scale of 0 to 100% (highest 32%).
| Day | High | Low | Chance of 0.01 in | Chance of 0.10 in |
|---|---|---|---|---|
| September 1 | 78°F | 62°F | 28% | 18% |
| September 8 | 76°F | 59°F | 29% | 18% |
| September 15 | 74°F | 57°F | 29% | 19% |
| September 22 | 71°F | 54°F | 31% | 19% |
| September 30 | 68°F | 51°F | 32% | 19% |
Every day of September: normal high, low and chance of precipitation (warmest afternoon September 1, coldest night September 30)
| Day | High | Low | Chance of 0.01 in | Chance of 0.10 in | Daylight |
|---|---|---|---|---|---|
| September 1 | 78°F | 62°F | 28% | 18% | 13 h 10 min |
| September 2 | 78°F | 61°F | 28% | 18% | 13 h 10 min |
| September 3 | 78°F | 61°F | 28% | 18% | 13 h 10 min |
| September 4 | 77°F | 61°F | 28% | 18% | 13 h 10 min |
| September 5 | 77°F | 60°F | 28% | 18% | 13 h |
| September 6 | 77°F | 60°F | 29% | 18% | 13 h |
| September 7 | 77°F | 60°F | 29% | 18% | 13 h |
| September 8 | 76°F | 59°F | 29% | 18% | 12 h 50 min |
| September 9 | 76°F | 59°F | 29% | 18% | 12 h 50 min |
| September 10 | 76°F | 59°F | 29% | 18% | 12 h 50 min |
| September 11 | 75°F | 58°F | 29% | 19% | 12 h 50 min |
| September 12 | 75°F | 58°F | 29% | 19% | 12 h 40 min |
| September 13 | 75°F | 58°F | 29% | 19% | 12 h 40 min |
| September 14 | 74°F | 57°F | 29% | 19% | 12 h 40 min |
| September 15 | 74°F | 57°F | 29% | 19% | 12 h 30 min |
| September 16 | 74°F | 56°F | 30% | 19% | 12 h 30 min |
| September 17 | 73°F | 56°F | 30% | 19% | 12 h 30 min |
| September 18 | 73°F | 56°F | 30% | 19% | 12 h 30 min |
| September 19 | 73°F | 55°F | 30% | 19% | 12 h 20 min |
| September 20 | 72°F | 55°F | 30% | 19% | 12 h 20 min |
| September 21 | 72°F | 54°F | 30% | 19% | 12 h 20 min |
| September 22 | 71°F | 54°F | 31% | 19% | 12 h 10 min |
| September 23 | 71°F | 54°F | 31% | 19% | 12 h 10 min |
| September 24 | 71°F | 53°F | 31% | 19% | 12 h 10 min |
| September 25 | 70°F | 53°F | 31% | 19% | 12 h 10 min |
| September 26 | 70°F | 52°F | 31% | 19% | 12 h |
| September 27 | 69°F | 52°F | 31% | 19% | 12 h |
| September 28 | 69°F | 52°F | 32% | 19% | 12 h |
| September 29 | 68°F | 51°F | 32% | 19% | 11 h 50 min |
| September 30 | 68°F | 51°F | 32% | 19% | 11 h 50 min |
- Normal high
- 74°FSeptember average
- Normal low
- 56°FSeptember average
- Precipitation
- 3.16 inmonth total
- Days with precipitation
- 90.01 inch or more
- Days at 90°F or more
- 1
- Daylight
- 13 h 10 min to 11 h 50 minSeptember 1 to September 30
- Days at 70°F or more
- 19
- Days at 80°F or more
- 7
- Sunshine
- 77%of clear-sky sunlight (NASA)
Source: NOAA NCEI 1991-2020 daily normals, station USW00014839; monthly normals. Daylight is computed from the place's latitude with NOAA's solar equations.
Does it rain in Milwaukee in September?
On a given September day the chance of 0.01 inch or more is 30% on average, highest around September 30 (32%). In all, 3.16 in falls on 9 days of a normal September, 1 of them with an inch or more.
In a normal September in Milwaukee, 1 days reach 90°F.
Source: NOAA NCEI 1991-2020 daily and monthly normals, station USW00014839.
How humid and windy is Milwaukee in September?
At 3 p.m. the normal temperature is 64°F with 56% relative humidity and a dew point of 48°F; at 6 a.m. it is 53°F with 80% humidity. The wind averages 9.6 mph, most often from the south-southwest in the afternoon. A dew point under 50°F feels dry.
| Time | Temperature | Dew point | Humidity | Wind | Clear or few clouds |
|---|---|---|---|---|---|
| 6 a.m. | 53°F | 47°F | 80% | 7.9 mph | 35% |
| 9 a.m. | 60°F | 48°F | 66% | 11.1 mph | 39% |
| noon | 64°F | 48°F | 56% | 12.3 mph | 28% |
| 3 p.m. | 64°F | 48°F | 56% | 12.4 mph | – |
| 6 p.m. | 60°F | 48°F | 65% | 8.6 mph | 31% |
| 9 p.m. | 57°F | 48°F | 72% | 8.3 mph | 54% |
Source: NOAA NCEI 1991-2020 hourly normals, station USW00014839. Hourly normals exist only for NOAA's first-order stations; a dash where NOAA publishes no value for that hour (the sky at some hours).
What are the records for September in Milwaukee?
The warmest September temperature on Milwaukee's official record (since 1871) is 99°F, on September 15, 1939; the coldest is 28°F, on September 28, 1942. The wettest September brought 9.87 in (1941).
The September mean against the 1991-2020 normal of 65.0°F: 2021 68.3°F (+3.3), 2022 66.3°F (+1.3), 2023 68.2°F (+3.2), 2024 68.0°F (+3.0), 2025 65.1°F (+0.1), 2026 65.9°F (+0.9). 6 of 6 ran warmer than normal.
| September | Mean | Against normal | Precip. |
|---|---|---|---|
| 2021 | 68.3°F | +3.3°F | 1.68 in |
| 2022 | 66.3°F | +1.3°F | 6.23 in |
| 2023 | 68.2°F | +3.2°F | 4.40 in |
| 2024 | 68.0°F | +3.0°F | 1.83 in |
| 2025 | 65.1°F | +0.1°F | 1.61 in |
| 2026 | 65.9°F | +0.9°F | 3.90 in |
Source: records: ACIS, NWS threaded record MKEthr; recent months: ACIS, station USW00014839. Records and recent months use complete months only.
How does September in Milwaukee compare across Wisconsin?
Across the 165 places PlainClimate covers in Wisconsin, September normal highs run from 64°F in Laona to 77°F in West Allis; Milwaukee's is 74°F.
Source: NOAA NCEI 1991-2020 monthly normals for every station in the state.
Other months and places
- Milwaukee in August80°F by day, 64°F at night
- Milwaukee in October61°F by day, 45°F at night
- Milwaukee through the yearEvery month, frost dates, records and recent years
- Wisconsin in SeptemberThe statewide normal and the warmest and coolest places
- West Allis: Wisconsin's warmest Septembernormal high 77°F